Self-locking nut and washer



Aug. 29, 1950 E, PUMMILL 2,520,259

SELF-LOCKING NUT AND WASHER Filed March 28, 1945 PI- 1 1 m z 515 5 1 514 516 517 1 523 flfl INVENT fDW/N 14 PUM 1..

same is the; bolt C9.

Patented Aug. 29, 1950 STATES PATENT OFFICE,

SEIiF-LOGKING NUT AND WASHER Edwin w. P-um-mill, Indianapolis, Ind.

ApplicationMal-ch 28, 1945, Serial No. 585,311

14 Claims. 1

This invention relates toaninitially integral washer and nut structure, subsequently separable in the threading home, of the structure upon a bolt-and the like and' th'en rigidly connected together, the washer serving as a :stock confining element int-he tightening ofthe'nut to form socalled full threads within at least-anappreciable Patent No. 2,3,80,99,;dated August 7, 1945.

The. full natureo'i "theinvention will be understood from the accompanying drawing and the following description and claims:

In the drawings,

Fist lis a central'secticnal viewf an embedimerit :oftheinventien after fabrication and "prior to. work application.

7 Fig, 2 :a similar view of such embodiment whcn-anpl dxtc the works nortionof thelatter being illustrated in sectionand the bolt associated herewith being-shown :in elevation.

Fig. Sis aiview'similar to 1 and of a cylindrical neck form of the invention Fig. 4 isia similar view-and or aslightly'modified form 0i cylindrical neck-embodiment of the inven ion.

Fig. 5 is/asimila-r view "of :a'modified form :of unit.

vFig. 6 is asimilar v'iew ofra :still further-modifiecl'iorm of unit.

In Fig. '2, oi'the drawings.A indicates: at-piece of work withuhole-B therein. "Brojectingfrom To the work exposed threaded-endofbolt C is applied'the integralnut and washer structure.

:Reierring to Eig'. 1, the structure, while 'sa'me may takelany onev of'severalrorms, isi-illustrated more ,particularly'asof :thetype shown initheasaid copendingrapnlicaction,with; .certainiexc'eptionsxas hereinafter pointed: out.

There :provided a nut bbdyiilil with la *gral with -=th-is hody and-at the washer confronting face 522 thereof i'sa neck por-tion li l z which, coaxial with the central bore '5 is provided with a threaded extension 513 of the same. may 'ext'en'd coextensive with the length of said *neck, seesaid copendi-ng application, or terminateshort of the washer end of'said neck, the latter herein having a bore enlargement 5 M as illustrated.

The washer' body 51 5 may have a -circular or polygonal exterior outline as desired. The diameter thereof may be as-desired. If thestructure is :of -bar stock and fabricated in an automatic screw machine, obviouslyit cannot be greater than that of the nut body.

"The washer body 51-5" on its work confronting face 516' includes a coaxial =c'c'ni'nter bore 517. said 'counter here at its outer end is enlarged as at ii-slay ch-amferingor the like and this relief or seat may take any desired form so that the radial sections thereof can be arcuate, .plane, or angular, as desired.

The neck is connected to the washer by frangible portion 519 and therein thelexter ior 520' of th'e neck may b'e' frust'oJuanita] as show'n, or' cyl'indrical as desired. ln'either itype when washer face-51E is engaged with workiA afternut fa lil Thas been :finger ithreadeddewn cn bolt C axiaI pressure applied to' friangih'lc';portion 52li9 by reason of "nut movement towardsithe work and ire- .sistance oftthe latter to ifunthermovement of the innit tasiza whole towwds "it, ruptures the unit. The washer is now free of the neck and nut, and. if the former :is zo'f .frusto-conical form 'it will immediately center the washer counter bore and locatethe washer.

If the neck is of frusto-conical character, further advance of sa'me hy' nut threading toward the work forms Ian annular ridgeabout the Washer on its nut. confronting face 521; which may be slopedasfldesired,or flatas illustrated, see the copending application. iDisregarding other actions which occur, when the washer-confronting 'face'5-Z2of nut'5 t0 engages th-is'annular ridge, the latter digs inwardly and upwardly into the neck at the neck-nut connection, which fences" the metal into full 'thread bolt contact forat least a thread *or so in the nut immediately adjacent face 522; This fa-ce a-l-s'o maybesloped as desired or flat as illustrated.

Between these stages nut advance causes the neck stock to-d'o two things, that 'is, circumferentially fill 'th'e counterbore 5H atthe ba'ck or n-ut end thereof and-causes full thread-contact =between threads 5t3-*a;nd the'bolt. As the threaded central bore 5 therethrought itnite- '55 nut is' threaded' hoine; this-counterh'oreprogressively fills up. The foregoing action is common to that disclosed in said application.

The action of this form of the invention now differs from the aforesaid application in that as the portion I9 advances into work engagement, the free end of the neck stock is forced radially outward. Enlargement 5l4 of the threaded bore 5l3 in the neck facilitates such action, although the enlargement may be omitted, if desired, with the same final result. i.

As shown in Fig. 2, stock from the washer end of neck 5| 2 flows outwardly and circumferentially fills seat 5|8 with the result that the nut and washer are now permanently locked together by portion 523, while the full thread formation is substantially, but not necessarily coextensive with the washer thickness, plus, it the frusto-conical neck be employed, at least onehalf to two or more full threads in the nut.

A neck 6l2 of cylindrical form, see Fig. 3, with or without the thread bore enlargement, and of a diameter slightly greater than that of the washer counterbore will function basically as last described. In this form, the cylindrical neck is progressively squeezed into bolt engagement as the nut is tightened down upon the bolt, the washer slightly yielding therefor.

A neck N2 of cylindrical form, see Fig. 4, with 01' without the thread bore enlargement, and of a diameter slightly less than that of the washer counterbore, will also function to a limited degree for full thread formation and fully function for seating and locking the bolt and washer together as last described. In this form of the invention it is axial pressure only between the nut and work that compresses the neck stock, which is washer confined as it flows into full thread formation, and also forms the seat lock aforesaid.

In Fig. 5 there is illustrated a modified form of the invention in which the neck portion M2 is frusto-conical, while counterbore 81'! is tapered inwardly and enlarged toward the neck.

The neck 8i2 and counterbore 8| I may have the same tapers or different tapers. If that of the neck 8 l 2 is more acute than that of the counterbore B, the washer compressive pressure on the neck 8l2 progressively increases as the nut 8H] is threaded upon the bolt and the neck 8|2 enters the counterbore 8". If the taper of the counterbore is more acute than that of the neck and the diameters of each are properly chosen, the washer initial compressive pressure on the neck is exerted adjacent the neck confronting face of the Washer for initially rolling up a. ridge thereon, which upon nut pressure being applied thereto digs into the neck 812 at its connection to the nut 810 to insure full thread formation in a part of the nut. Of course, in both forms final nut threading forces the neck stock at its free end outwardly to engage seat 958, comparable to that illustrated in Fig. 2 at 523, and thus again lock the washer to the nut by a clamping action.

When the dogging in lock is effected, the peening lock (see portion 523 in Fig. 2) may be omitted or utilized as desired. When dogging in is not effected, the full thread formation in the nut may not occur, but full thread formation does occur in the compressed neck portion by reason of washer confinement of compressed neck stock. The locking connection is positively maintained by the confining pressure exerted between the seat engaging portion and the nut for .clamping the washer therebetween. As previously stated, either or both washer-nut locks may be utilized as desired or required for special connections.

In Fig. 6 there is illustrated a modified form of unit. In this form the neck M2 is cylindrical as in Figs. 3 and 4 and the counterbore 9|! is tapered as in Fig. 5.

This forces the washer stock to compress inwardly the neck stock and progressively. This also facilitates axial advance of the cylindrical neck 9|2 into the washer counterbore 9|! and centers the washer 9l5 upon the neck 912 and bolt. When the free end of the neck engages the work, further nut advance forces that neck stock outwardly and circumferentially and into washer seat 918 contact. Thus, th washer at the neck confining portion will be clamped between the nut body QIU and the seat engaging portion of the neck stock comparable to portion 523 in Fig. 2.

The washer clamping action is such, in all these forms of the invention, that the volume of the neck stock must be at least sufllcient to fill the counterbore axially and circumferentially and at least partially fill circumferentially the seat 5i8 in washer face 5 i (i suificient to clamp the washer 515 between the stock 523 and the nut Sit. In all modifications (although in Fig. 4 to a lesser degree) there is a swelling or diametral increase in the washer.

While the invention has been illustrated and described in great detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character.

The several modifications described herein as well as others which will readily suggest themselves to persons skilled in this art, all are considered to be within the broad scope of the invention, reference being had to the appended claims.

The invention claimed is:

1. In an initially integral nut and washer structure having a nut body with a threaded bore therethrough, a neck integral at one end with the nut body and having a bore therethrough aligned with the first bore and threaded for at least the major portion and forming a. continuation of the nut body thread, the neck at any cross section having a maximum circumscribing diameter less than that of the nut body diameter, and a washer body at one end initially integral with the neck at other end thereof and having a counterbore opening at the washer body other end and communicating at its inner end with the neck threaded bore, the diameter of the counterbore at its inner end being but slightly less than the diameter of the neck adjacent the washer body, the end of the counterbore ter minating in proximity to and but slightly spaced from the neck to define a readily rupturable neck-washer connection, the counterbore nesting the neck when axial pressure is applied to the nut and the washer said other end is work engaged, the said washer-neck connection being severable by relative axial movement between the washer and neck, the counterbore of said washer at the said other end having a chamfer forming a seat, the neck being of such length that, when counterbore nested, it has its ruptured end deformed outwardly and laterally by work engagement into seat association to clamp the washer body between that enlargement and the nut body when the two bodies are in intimate facial contact.

2. A structure as defined by claim 1 wherein the counterbore initially of tapered character.

3. A structure as defined by claim 1 wherein the neck exterior initially is of cylindrical character.

4. A structure as defined by claim 1 wherein the neck exterior initially is of frusto-conical character.

5. A structure as defined by claim 1 wherein the counterbore initially is of cylindrical character.

6. A structure as defined by claim 1 wherein the counterbore initially is of cylindrical character and the neck exterior initially is of frustoconical character.

7. A structure as defined by claim 1 wherein the counterbore initially is of cylindrical character and the neck exterior initially is of cylindrical character.

8. A structure as defined by claim 1 wherein the counterbore initially is of tapered character and the neck exterior initially is of frusto-conical character.

9. A structure as defined by claim 1 wherein the counterbore initially is of tapered character and the neck exterior initially is of cylindrical character.

10. Structure as defined by claim 1 wherein parallel sections of the neck and washer transverse to the nut axis are defined by a neck exterior surface circle and a washer interior counterbore surface circle, certain of said circles having the same diameter.

11. Structure as defined by claim 1 wherein parallel sections of the neck and washer transverse to the nut axis are defined by a neck exterior surface circle and a washer interior counterbore surface circle, certain of the circles having different diameters,

12. Structure as defined by claim 1 wherein parallel sections of the neck and washer transverse to the nut axis are defined by a neck exterior surface circle and a washer interior counterbore surface circle, certain ofthe circles having different diameters, at least one of the washer section circles being of greater diameter than the diameter of the smallest neck section circle.

13. Structure as defined by claim 1 wherein parallel sections of the neck and washer transverse to the nut axis are defined by a neck exterior surface circle and a washer interior counterbore surface circle, certain of the circles having different diameters, at least one of the washer section circles being of lesser diameter than the diameter of the largest neck section circle.

14. Structure as defined by claim 1 wherein the neck adjacent the counterbore is provided with a counterbore of lesser diameter than the washer counterbore for stock reduction of the neck at the frangible connection between the neck and washer body.

EDWIN W. PUMMILL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 256,767 Timby Apr. 18, 1882 642,375 Simpson Jan. 30, 1900 1,875,930 Martin Sept. 6, 1932 1,928,769 Teetor Oct. 3, 1933 1,945,005 Vacher Jan. 30, 1934 2,285,080 Berge June 2, 1942 2,380,994 Pummill Aug. 7, 1945 

